> >The caller might not appreciate what you've done to their 
> stack though.
> 
> ?? Why should the caller care? He called you. You invoked 
> prim 1 on something. You returned a result. The caller has his answer.

Excellent point.  But, generally you expect a message to leave only one
result on the stack.  True that it won't hurt anything...but the call
leaves you (the calling context) a little bit bloated.

- Stephen